Sparking plug



A. GAZDA S PARK ING PLUG Sept. 5, 1939.

Filed March 7, 1938 Patented Sept; 5,1939

PATENron-ms 231,929 srannmo PLUG Anton Gazda, -l.ondon, England Application March 7, 1938, semi No. 194,471

' In Great Britain May a, 1937 4 Claims (01. 123-169 Frequently it is the case, that the sparking plugs of internal combustion engines get out of order owing to excessive heating, for instance if the insulator, enclosing the concentrically placed,

5 electrode, crackswhich' may be dangerous particularly in the case of flying machine engines.

In order to prevent excessive heating of the sparking plugs it has been proposed heretofore to provide a hollow central electrode which wholly or'in part vis charged with a heat absorbing cooling medium. Further it has been proposed to make hollow the metallic bodycf the plug and charge the's'ame with a cooling medium.

.The present invention relates to improvements in sparking plugs of the kind in which the central electrode is surrounded by an insulator and cooled by a heat absorbing cooling medium and its essential feature consists in that that the insulator v surrounding thecentral electrode is made hol- 30 low and charged with the heat absorbing cooling medium.

, ,One mode of carrying out the present invention is illustrated by way of example in sectional elevation inthe accompanying drawing,

The sparking plug, shown 1n axial longitudinal section, is providediwith a central electrode a, which is enclosed in an insulator b for instance of porcelain, secured in known manner by. a nut c to its seat in the plug-casing e, which carries the mass-electrode d. Over its entir'e'length, theiin sulator b is provided'with an annular hollow space bkwhich is closed at all sides and is filled with a non-evaporating, solid but liquidable and heat absorbing cooling medium I which during the operation of theinternal cbmbusion engine absorbs the heat, fuses and becomes liquid and which, owingto 'the shocks t'o'which said engine is exposdgmovesabout within the hollow space I b, in order to cool the insulator. For instance al-- m kaline metallic salts, which'are liqueflable at the temperature to which the sparking plug 'issub- :Iected, are adapted for use as heat absorbing cooling media; the temperature of evaporation of said salts being higher than the temperature to, 4,5 which the sparking plug ever is subjected; Furtherv convenient cooling media arei'or instance- Compared with the hitherto known sparking plugs, the sparking plug above described is more reliable and has a longer life in view of its special construction for attaining an effective cooling.

What I claim is 5 1, A sparking plug comprising in combination, a double-walled hollow insulator which is closed at both 'ends and thus forms an entirely closed hollow casing with a central passage bounded bythe innerwall of said insulator, a central 0 electrodeextendlng through and out of said passage, a plug casing secured to the outside of said insulator, and a mass-electrode fixed to said plug casing.

2. A sparking plug comprising in combination, 15 a double-walled hollow insulatornwhich is closed at both ends and thus forms an, entirely closed hollow casing with a central passage bounded by the inner wall of said insulator, a central electrode extending through and out of said passage, 20

a double-walled hollow plug' casing secured to said insulator, said plug casing being closed at both ends and thus forms an entirely closed 'hol-,

low casing with a central passage bounded by the inner wall of said-plug casing, and a mass-elecg5 trode fixed to said plug 3. -A sparking plug comprising in combination, a double-walled hollow insulator which is closed at both ends and thus forms an entirely closed hollow casing with a central passage bounded by so the-inner wall of said insulator','a heat absorbing cooling medium in said hollow insulator, a central electrodeextendlng through and out of said passage, a plug casing secured to the outside of said insulator, and a mass-electrode ilxedto said as plug casing.

4. A sparking plug comprising in combination, a double-walled hollow insulator which is closed at both ends and thus forms "an entirely closed hollow casing with a central passage bounded by so the inner'wall of said insulator, a central electrode extending through and out of said passage, a double-walled hollow plug casing secured to' said insulator, said plug casing being closed at both ends and thus forms an. entirely closed I nouow casing with a central-passage bounded by I the inner wall of said plug casing, a heat absorbing cooling medium in said hollow insulator and in said hollow'plug casing, and a mass-electrode fl'xed to said plug casing. so

ANTON GAZDA. 

